The invention of the present application pertains to an earth ground terminal which is used to prevent electromagnetic inductive interference, high-frequency inductive interference, etc. when a printed substrate is ground by another printed substrate, a shield plate, a chassis, a case (frame), etc.
Japanese Kokai Patent Application No. Hei 9[1997]-115574 disclosed a connection terminal as an example of the prior type of earth ground terminal. FIG. 6 shows the state when the connection terminal is soldered to a printed circuit board. For the aforementioned connection terminal, a pair of soldering parts 6 and 7 are set up appropriately at different positions along the same straight line in the longitudinal direction of connection part 4 so that the inner surfaces of the soldering parts face each other. In this way, the solder can expand in such a direction that the surface tension of the solder in soldering parts 6 and 7 cancel each other. Therefore, position deviation can be prevented during soldering.
However, when the aforementioned connection terminal is soldered to the printed circuit board, it is difficult to determine by visual observation whether the solder fillet is reliably attached to the soldering parts. It is especially difficult to make the aforementioned determination for soldering part 7 which is covered by connection part (spring contact) 2. Also, a small terminal makes it more difficult to make the aforementioned determination.
The purpose of the invention of the present invention is to solve the aforementioned problem by providing a small and inexpensive earth ground terminal whose soldering state can be confirmed easily.
In order to realize the aforementioned purpose, the invention of the present application provides an earth ground terminal characterized by the fact that the earth ground terminal comprises an electroconductive substrate part and an electroconductive spring contact which protrudes integrally from one edge of the substrate part toward the side opposite to the substrate part, and through holes that have undergone a burring process are formed in the substrate part.